Textile spindle



March 19, 1968 H. H. RICHTER TEXTILE SPINDLE 2 Sheets-Sheet 1 Filed June 21, 1966 FIG.5

INVENTOR HANS H. RICHTER W F l G. 4

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ATTORNEYS FIG.3

March 19, 1968 H. H. RICHTER 3,373,555

' TEXTILE SPINDLE Filed June 21, 1966 v 2 Sheets-Sheet 2 70 Q V W V. 80 I fi llllLL' I j nnnnnnr=g| I /787 82 3O Fl G. 7

INVENTOR.

HANS H. RICHTER W f \DM W WW2.)

ATTORNEYS United States Patent fiice 3,3 73 ,555 Patented Mar. 19, 1968 3,373,555 TEXTILE SPINDLE Hans H. Richter, Cranston, RJL, assignor to Lessena Corporation, Warwick, R.I., a corporation of Massachusetts Continuation-in-part of application Ser. No. 501,140, Oct. 22, 1965. This application June 21, 1966, Ser. No. 555,868

21 Claims. (Cl. 5777.45)

This application is a continuation-in-part of copending application Ser. No. 501,140, filed Oct. 22, 1965, now abandoned.

This invention relates generally to apparatus for imparting false twist to a strand of yarn, and more particularly is directed to a novel high speed false twist spindle for use with such apparatus.

A variety of techniques have been proposed for imparting a crimped structure to yarns but at the present time only one is being used on a widespread scale. This procedure involves twisting the yarn, setting the twist as by a heater, and untwisting the set yarn in a continuous operation which is accomplished by passing the yarn through a rotating body having some means for engaging the yarn to prevent free twist migration, rotation of the body imparting twist in one direction in the yarn on one side of the body and twist in the opposite direction on the other side thereof. A temporary twist is inserted in the yarn, the twist is heat set and then removed therefrom as the yarn travels past the body. Spindles adapted for this operation have come to be known as false twist spindles in contrast to true twist spindles which rotate either the delivery or take-up yarn packages.

The particular spindle disclosed herein, while completely operable for false twisting synthetic yarns, has particular adaptability for use with fibrous textile yarns such as cotton which inherently have a lower tensile strength than a filament yarn such as nylon. As the result of their lower tensile strength, fibrous yarns are much more susceptible to breakage during the false twist process and so heretofore have required reduced spindle speeds to maintain tension at a minimum and at a constant value.

Prior art false twist spindles which have found limited application in the processing of fibrous yarns have employed wheels or sheaves for receiving yarn thereabout to arrest or trap the twist. These wheels or sheaves are commonly mounted rotatably on a head member which itself rotates. The wheel design has been found to be particularly undesirable for use with fibrous yarns because of the relatively high friction induced between the wheel and its mounting pin, and centrifugal force tending to hold the wheel in engagement with one of the ears of the rotating head. Still other spindles employ twist trapping arrangements including the use of pins in various numbers and configurations extending across the bore of a rotating head member. However, all of the devices investigated have serious drawbacks which are considerably reduced or eliminated by the application of the present invention.

It will be appreciated therefore, that it is desirable to maintain the tension in the yarn on the exit side or upstream of the false twist spindle at or very near to that present at the inlet or downstream side of said spindle. Simultaneously, although it is desired to maintain a relatively low yarn tension adjacent the inlet side of the spindle, that is, in the heat setting Zone it is necessary that the yarn tension not decrease below a certain predetermined level. Conventional spindles have been ineffective in controlling the tension of the yarn at these two locations to desired values. The present invention has unique capability in correcting this deficiency in the false twist spindles of the prior art.

One object of the invention is to provide a false twist spindle which maintains an upstream yarn tension sub stantially the same as the downstream yarn tension.

Another object of the present invention is to provide a false twist spindle which is capable of processing both synthetic and fibrous yarns.

A further object of this invention is the provision of a false twist spindle having an increased economy of operation.

Yet another object of the invention is to provide a false twist spindle operable at higher speeds of rotation without exceptional wear or overheating.

Still a further object is the provision of a novel false twist spindle which compensates for an undesirably re duced tension prior to entry of the yarn into the spindle by automatically increasing the rate of feed therethrough.

Still another object is to provide a novel false twist spindle having two cooperating elements, one being a rotatable twister head, the other being a hollow feed pin.

Other and further objects will become more apparent upon a reading of the specification which follows taken together with the drawings in which like numerals refer to like parts throughout.

In the drawings:

FIG. 1 is a perspective view generally illustrative of the novel false twist spindle;

FIG. 2 is a perspective view of the cooperating twister head and feeder pin with a yarn threaded thereon;

FIG. 3 is a side elevation View twister head and feeder pin;

FIG. 4 is a view in section illustrating the bearing support structure for the feeder pin;

FIG. 5 is a top plan view generally taken along lines 55 of FIG. 3;

FIG. 6 is a detail view, partly in section, showing a modification of the feed tube assembly; and

FIG. 7 is a detail view, partly in section, showing still another modification of the feed tube assembly.

With reference now to the drawings, and particularly to FIG. 1 thereof, the false twist spindle of the instant invention is indicated by numeral Ill. A housing 12 of known construction is provided as a base for the rotating elements and operates to selectively swing the spindle from an operative to an inoperative position about a horizontal axis.

A hollow spindle 14 is rotatably mounted in a conventional manner in bearings 16 which are held fixed at one end by means of nut 18. Suitably mounted to the uppermost end of spindle 14 for rotation thereon is the first main element of the false twist spindle, indicated at 20 and referred to as the twister head. A central portion of the twister head 2% has been removed, resulting in a pair of upstanding ears 22 formed with substantially parallel inner walls 24-. Extending between the walls 24 and fixed at the ends to ears 22 is a pair of generally parallel guide members 26 and 28, respectively, member 26 disposed somewhat higher than member 28, as is best seen in FIG. 3.

With particular reference now to FIG. 1, an upstanding, L-shaped bracket member 30 is seen mounted to housing 12 by means of nut 18. The lower portion of spindle 14 functions as a whorl and is engageable by a spindle driving belt (not shown). With reference now to FIG. 4, there is secured to bracket 30 by means of screws 32 a mounting block 34 housing a pair of precision ball bearings 36 held in spaced apart relationship by means of sleeve 38. The inner races of the bearings 36 are we vented from sliding out of engagement with sleeve 38 by means of cap members 40 which are fittingly received on a feed tube 42. An internal chamfer is provided at the ends of feed tube 42 to prevent wearing or abrasion of of the cooperating the yarn as it passes through internal recess 43 in a manner to be subsequently described. Likewise, sleeve 38 and the inner races of the ball bearings are received on the tube 42 in a press fit.

In a similar manner, the outer races of the ball bearings 36 are press fitted into the side walls of bore 44 formed in mounting block 34. A spacer 46 is received within bore 44 intermediately of bearings 36. Between each set of ball bearings 36 and spacer 46 is received a pair of cupped spring washers 48 disposed in back-to-back relationship for the purpose of pre-loading the bearings whereby to prevent a wobble or oscillating motion of feed tube 42 as it rotates with respect to mounting block 34. A set screw 50 when tightened down serves to hold spacer 46 fast to the mounting block.

A unique false twist, high speed spindle has thus been described having two independent rotating elements, viz., the twister head 20 and the feed tube 42. An explanation of the manner in which these two elements cooperate to impart a false twist in a strand of yarn passing there through will now be provided.

FIGS. 2, 3 and 5 should now be referred to, as each of these discloses a yarn Y in cooperation with the false twist spindle of the instant invention. A strand of yarn Y is seento pass upwardly through shaft 14 arriving therein after passing through the heating elements (not shown) of a conventional false twisting machine. The yarn is seen to pass into the area between the cars 22, thence over guide member 26, looped once around feed tube 42, over and around guide member 28, and into and through tube 42. As the yarn exits from the top end of feed tube 42, it is directed onto a take-up package either directly or from a feed roll (neither shown) drawing the yarn therethrough in a conventional manner.

Twister head is rotated in the customary manner by a rapidly translating drive belt (not shown) engaging the whorl of spindle 14, and as viewed in FIG. 5 spins in a counterclockwise direction to impart a Z-twist to the yarn.

Although the yarn is seen in FIG. 5 to be twisted about tube 42 in a clockwise direction, as indicated by the arrow, it may also be threaded in a counterclockwise direction. In the latter event, twister head 20 is spun in a clockwise direction whereby S-twist is imparted to the yarn. It is to be appreciated that the yarn passing over guide members 26 and 28 is wrapped once around feed tube 42 in such a manner that, by reason of the frictional engagement on said tube, yarn is drawn upward from spindle 14, over guide member 26, and fed over guide member 28 into the interior recess of tube 42. Were there no friction in bearings 36 and with the feed roll held inactive, said tube would rotate in the same direction and at the same rate of speed as twister head 20. In this instance, because there is no relative angular velocity difference between twister head 20 and feed tube 42, the former neither wraps yarn onto nor unwraps yarn from the latter. Thus yarn is neither advanced nor withdrawn through the spindle by the mutual action of the two cooperating elements 20 and 42. However, in practice, friction is present in the bearings 36 so that tube 42 rotates at a somewhat slower rate than does the twister head. In this instance, yarn is physically wrapped around the slower rotating tube 42 by the faster rotating twister head 20 and thereby fed up through the interior recess 43 for eventual winding onto the take-up roll.

As previously related, the primary reason for development of the spindle herein is to maintain yarn tension upstream and downstream therefrom at relatively constant and acceptable levels. Thus, it will be appreciated that when tension decreases downstream of the spindle 14, the frictional engagement of the yarn Y wrapped about feed tube 42 likewise decreases. Consequently, feed tube 42 slows down resulting in a higher rate of yarn feed therethrough, which increases the tension on the yarn, raising it to an acceptable, predetermined level. Conversely, should the tension increase downstream of the spindle, the wrap of the yarn Y about feed tube 42 is made tighter thus speeding up said feed tube, but reducing the rate of feed of yarn therethrough. The result is to reduce yarn tension downstream of the spindle to an acceptable, predetermined level. In all instances presented herein, the predetermined level of yarn tension is dependent upon the amount of preload applied to the bearings by means of spring washers 48. The greater the preload, the slower will rotate feed tube 42 relative to twister head 24 with the consequent variation in rate of yarn feed therethrough.

Throughout this discussion, it should be borne in mind that yarn tension is a function of yarn length. Thus, for example, should a strand of yarn have even minute variations in denier, it is obvious that the heavier portions, when crimped or twisted, will shorten to a greater extent than the lighter portions with resulting higher tensions in the shortened portions. Hence, the two element spindle described serves to compensate for yarn variations in a manner totally unknown heretofore.

Even with only one wrap of yarn passed around feed tube 42, twist migration is negligible, the spindle herein serving as a far more effective twist trapping device than earlier spindles. However, it will be apparent that a plurality of wraps could be employed if desired. Furthermore, the tension upstream of the spindle is substantially reduced from that of earlier spindles because of the reduced friction inherent in the design of the new spindle and because of the positive feed of yarn therethrough by the cooperating twister head 20 and feed pin 42. Also, knots and loops in the yarn will pass through the spindle with ease contrary to the operation of prior art spindles, particularly when one turn of yarn around tube 42 is used.

A modified embodiment of the invention is illustrated in FIG. 6 which presents structure for restricting the rotational speed of feed tube 42. This additional structure is complementary to spring washers 48 which serve to preload bearings 36 and thereby control the rotation of said feed tube. It is generally desirable to permit the substantially unhindered rotation of feed tube 42 by means of the advancing yarn Y which is wrapped thereabout and which passes therethrough. However, in some instances it has been found advantageous to reduce the rotational speed of feed tube 42 or even to stop rotation of said feed tube during operation of the spindle. It has been explained previously that the yarn Y is not advanced by the spindle when the feed tube 42 is rotated by the engaging yarn at a speed equal to that of the spindle 14. Further, it will be understood that the feed rate of yarn Y advancing through tube 42 increases as said tube slows relative to spindle 14, and is greatest when tube 42 is held stationary.

To the end that additional speed control of tube 42 is achieved, the structure illustrated in FIGS. 1 and 4 has been modified such that bracket 30 is provided with an extension 52. A support block 54 is secured to extension 52 as by welding or the like and has a bore 56 suitably formed therein. A brake element 58, preferably composed of a wear-resistant, non-abrasive material such as that marketed under the registered trademark of Teflon, is snugly received within bore 56. One end of said element is arcuately formed to fittingly engage the peripheral surface of cap member 40 while the other end is engaged by a compression spring 60. Support block 54 is drilled and tapped as at 62 to receive a screw 64 which, through an independent spacer 66, engages the end of spring 60 opposite brake element 58.

It will be appreciated that the farther screw 64 is turned into block 54 and therefore the more spring 60 is depressed, the greater will be the load imparted to the cap member 40 by the brake element 58.

The spring 60 is desirably chosen such that there is substantially no restraint of rotation of feed tube 42 by the brake element 58 with screw 64 fully retracted while said feed tube is held fixed against rotation when screw 64 is fully inserted.

FIG. 7 discloses a somewhat different arrangement from that illustrated in FIG. 6, but which operates in substantially the same manner. In this embodiment, feed tube 42 extends some distance above mounting block 34, the upper extension of tube 42 being referenced at 68. A disc 70 composed of any suitable magnetic material such as iron is mounted as by a force fit at the uppermost end of the extension 68. Bracket member 30 likewise is formed with an extension 72 which terminates in a substantially horizontal platform 74. Said platform mounts a support block 76 which may be fixed thereto as by welding or other suitable fastening means. A smooth bore 78 is formed in the block 76 as is a drilled and tapped bore 80 which receives screw 82 therein.

One end of a C-shaped permanent magnet 84 is connected to screw 82 by means of a ball joint 36 while a rod 88 integral with said magnet is slidably received in smooth bore 78. The north pole N of magnet 84 is seen to overlie disc 70 and the south pole S underlies said disc, the spacing between the poles and the disc being only sufficient to permit relative movement therebetween and to allow for any eccentricity in the disc 7 0.

It will be apparent that rotation of screw 82 serves to adjust the radial disposition of magnet 84 relative to the magnetic disc 76, In a well known manner, the magnet 34 serves to impede the rotational movement of feed tube 42. With the poles of the magnet contiguous with the outermost radial regions of disc 70, rotation of feed tube 42 will be retarded to the maximum extent such that the rate of yarn advancement is a maximum. Conversely, with the poles of the magnet 84 overlying the innermost regions of disc 70, rotation of feed tube 42 will be only lightly retarded to a minimal extent such that the rate of yarn advancement is a minimum.

Accordingly, a novel false twist spindle has been described which is particularly applicable for operating on fibrous yarns such as cotton which are considerably more fragile than the continuous filament yarns such as nylon. The invention is of a design which compensates for yarns having irregularities which would cause variations in the tension thereof as they are fed first through the heaters and then through the false twist spindle. The new spindle operates to reduce undesirably high tensions and to increase undesirably low tensions downstream thereof, while maintaining as low a tension upstream thereof as possible. The new spindle is capable of producing crimped yarns of improved quality at greatly increased speeds while at the same time reducing to a considerable degree the amount of down time resulting from frequent yarn breakage.

Since certain changes may be made in the abovedescribed apparatus without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense; further that the invention is only to be limited by the spirit and scope of the claims hereunto appended.

What is claimed is:

1. A device for twisting-untwisting yarn comprising, a rotatable spindle having an axial bore therethrough for passage of a moving strand of yarn, means for rotating said spindle, means for rotating said yarn in response to rotation of the spindle to twist-untwist the yarn, and a rotatable tube having at least a portion of its external surface arranged to engage the yarn moving from said spindle, said tube being rotated in response to engagement by said moving yarn to advance said yarn from said spindle.

2, A device according to claim 1 including means for controlling the rotation of said tube.

3. A device according to claim 2 wherein said spindle includes a section of magnetic material, and said controlling means includes a magnet contiguous to said section, and means to adjust said magnet relative to said section.

4. A device according to claim 1 wherein said yarn rotating means includes pin means located to engage the yarn moving from said spindle and direct it in a path substantially normal to its path of movement through said axial bore.

5. A device according to claim 2 wherein said controlling means comprises a brake arranged to engage said tube and means to adjust the action of said brake on said tube.

6. A device according to claim 4 wherein the portion of said tube receiving the yarn is disposed in the plane of movement of said pin means.

7. A device according to claim 6 wherein said rotatable tube is provided with an axial bore therethrough, the axial bore of said tube being aligned with the bore through said spindle, said bore through said tube acting to receive the yarn advanced by said tube.

8. Apparatus as set forth in claim 11 including bearing means for rotatably supporting said tube, and means for preloading said bearing means to control the rate of rotation of said tube.

9. A device according to claim 11 wherein said yarn rotating means includes pin means located to engage the yarn moving from said spindle and direct it in a path substantially normal to its path of movement through said axial bore.

it A device according to claim 7 wherein said controlling means comprises a brake arranged to engage said tube and means to adjust the action of said brake on said tube.

11. Apparatus for twisting-untwisting yarn comprising, a housing, a rotatable spindle having an axial bore therethrough for passage of a moving strand of yarn, bearing means supporting said spindle in said housing for rotation, means for rotating said spindle, means for rotating the yarn in response to spindle rotation to twist-untwist said yarn, a tube rotatably supported in said housing in a location spaced from said spindle, said tube having at least a portion of its external surface arranged to engage the yarn moving from said spindle, said tube being rotated in response to engagement by said moving yarn, and means for controlling the rate of rotation of said tube to increase the rate of yarn movement from said spindle when tension in the yarn entering the spindle decreases below a predetermined value and to decrease the rate of yarn movement from said spindle when tension in the yarn entering the spindle exceeds a predetermined value.

12. A device according to claim 14 wherein said rotatable tube is provided with an axial bore therethrough, the axial bore of said tube being aligned with the bore through said spindle, said bore through said tube acting to receive the yarn advanced by said tube.

13. A device according to claim 11 wherein said spindle includes a section of magnetic material, and said controlling means includes a magnet contiguous to said section, and means to adjust said magnet relative to said section.

14. A device according to claim 9 wherein the portion of said tube receiving the yarn is disposed in the plane of movement of said pin means.

15. Apparatus for twisting-untwisting yarn comprising, a housing, a rotatable spindle blade having an axial bore therethrough for passage of a moving strand of yarn, bearing means supporting said spindle blade in said housing for rotation, means for rotating said spindle blade, a twister head having a central aperture therethrough, said head being connected with said blade for rotation with said aperture aligned with said bore, said head including first and second yarn guide members for engaging the yarn and to twist-untwist the yarn in response to rotation of said spindle, said first guide member being disposed in a position closer to said blade than second guide member, a tube rotatably supported in said housing in a location spaced from said twister head, said tube having at least a portion of its external surface arranged to engage the yarn moving from said twister head, said tube being rotated in response to engagement by said moving yarn, and means for controlling the rate of rotation of said tube to increase the rate of yarn movement from said twister head when tension in the yarn entering the spindle decreases below a predetermined value and to decrease the rate of movement from said twister head when tension in the yarn entering the spindle exceeds a predetermined value.

16. Apparatus as set forth in claim 15 including bearing means for rotatably supporting said tube, and means for preloading said bearing means to control the rate of rotation of said tube.

17. A device according to claim 15 wherein said yarn rotating means includes pin means located to engage the yarn moving from said spindle and direct it in a path substantially normal to its path of movement through said axial bore.

18. A device according to claim 17 wherein the portion of said tube receiving the yarn is disposed in the plane of movement of said pin means.

19. A device according to claim 18 wherein said rotatable tube is provided with an axial bore therethrough, the axial bore of said tube being aligned with the bore through said spindle, said bore through said tube acting to receive the yarn advanced by said tube.

20. A device according to claim 15 wherein said controlling means comprises a brake arranged to engage said tube and means to adjust the action of said brake on said tube.

21. A device according to claim 15 wherein said spindle includes a section of magnetic material, and said controlling means includes a magnet contiguous to said section, and means to adjust said magnet relative to said section.

References Cited UNITED STATES PATENTS 2,791,086 5/1957 Hilbert et a1. 5777.45 3,035,399 5/1962 Scragg 57-77.45 3,044,247 7/1962 Hilbert 5777.45 3,330,104 7/1967 Dunwoody 5777.3 XR

OTHER REFERENCES 1,169,861 1/ 1957 France.

760,261 10/ 1956 Great Britain. 1,025,006 4/1966 Great Britain.

FRANK J. COHEN, Primary Examiner.

D. WATKINS, Examiner. 

1. A DEVICE FOR TWISTING-UNTWISTING YARN COMPRISING, A ROTATABLE SPINDLE HAVING AN AXIAL BORE THERETHROUGH FOR PASSAGE OF A MOVING STRAND OF YARN, MEANS FOR ROTATING SAID SPINDLE, MEANS FOR ROTATING SAID YARN IN RESPONSE TO ROTATION OF THE SPINDLE TO TWIST-UNTWIST THE YARN, AND A ROTATABLE TUBE HAVING AT LEAST A PORTION OF ITS EXTERNAL SURFACE ARRANGED TO ENGAGE THE YARN MOVING FROM SAID SPINDLE, SAID TUBE BEING ROTATED IN RESPONSE TO ENGAGEMENT BY SAID MOVING YARN TO ADVANCE SAID YARN FROM SAID SPINDLE. 